Electronic devices, including portable electronic devices, have gained widespread use and can provide a variety of functions including, for example, telephonic, electronic messaging and other personal information manager (PIM) application functions. Portable electronic devices can include several types of devices including mobile stations such as simple cellular telephones, smart telephones, wireless PDAs, and laptop computers with wireless 802.11 or Bluetooth capabilities. These devices run on a wide variety of networks from data-only networks such as Mobitex and DataTAC to complex voice and data networks such as GSM/GPRS, CDMA, EDGE, UMTS and CDMA2000 networks.
Devices such as PDAs or smart telephones are generally intended for handheld use and ease of portability. Smaller devices are generally desirable for portability. Touch screen devices constructed of a display, such as a liquid crystal display, with a touch-sensitive overlay are useful on such handheld devices as such handheld devices are small and are therefore limited in space available for user input and output devices. Further, the screen content on the touch screen devices can be modified depending on the functions and operations being performed.
These touch-screen devices suffer from disadvantages, however, as the resolution of such touch-screen devices is limited when determining multiple touch inputs. When two closely-spaced options are selected from a graphical user interface, particularly when the second option is selected by touching while the user is still touching the touch screen display at the first option, the user-selected options are not correctly determined. Instead, a single touch input is commonly detected, rather than multiple touch inputs. Further, resolution of the touch-screen devices is insufficient to determine which of the options the user is attempting to select when closely-spaced, adjacent options are touched. This is particularly problematic when, for example, virtual keyboards are provided for user-selection of virtual buttons as selection of adjacent buttons on the keyboard is not correctly resolved.
Improvements in portable electronic devices are therefore desirable.